Typewriter mechanism



'0. A. HOKANSON. TYPEWRITER MECHANISM.

APPLICATION FILED units, 1920. I

I Patented July 26, 1921.

Fig.8 7 Z 9Z 4m 1 I I 1 I 55 59 UNITED STATES PATENT, OFFICE}.

OTTO A. HOKANSON, OF WOODSTOCK, ILLINOIS, ASSIGN 'OR TO WOODSTOCK TYIE- WRITER COMPANY, OF WOODSTOCK, ILLINOIS, A CORPORATION OF ILLINOIS.

TYPE-WRITER MECHANISM.

7 Specification of Letters Patent. Patented July 26!, 1921 Application filed March 15, 1920. Serial No. 365,966.

T all whom it may concern:

Be it known that I, Orrro A. HOKANSON, a citizen of the United States, residing at Woodstock, in the county of McHenry and State of Illinois, have invented certain new and useful Improvements in Typewriter Mechanism, of which the following is a specification. This invention has for its object the pro vision of typewriter mechanism which shall be of approved construction and operation. The invention is exemplified in the arrangement of parts shown in the accompanying drawing and described in the following specification and it is more particularly pointed out in the appended claims.

In the drawing Figure 1 is a fragmentary sectional view of a portion of a typewriter illustrating one embodiment of'the present invention.

Fig. 2 is a vertical section on line 2-2, Fi l.

Fig. 3 is a fragmentary View showing a detail of construction.

In the drawings designates a type bar segment having the usual bars 11 pivotally mounted thereon by means of a pivot rod 12 lying in a recess in the type bar segment 10. The usual platen 13 is provided to form n a backing against which the type strike. The type bar segment 10 is provided wlth a series of slots 14 in which the lower portions 15 of type bars 11 are mounted; Each bar.

11 is provided with a hook 15 for engagin the pivot rod 12 and a second longer hoo portion 16 for receiving a pivot pin 17 carried by a link 18 connected with the key lever mechanism in any usual and approved manner.

The type bar segment 10 is provided with an arcuate recess or notch 19 which follows the contour of the type bar segment and in which a universal bar 20 normally reposes. The universal bar 20 has the curved outline of the type bar segment 10 so that it follows the contour of the recess 19. Each type bar 11 is provided with a projection 21 arranged to engage the universal bar 20 when the type bar is moved into printing position and forces the bar 20 rearwardly or to the right as viewed in Fig. 1 of the drawing. The movement of the bar 20 under the impact of the type bar 11 is resisted by a spring, not shown, which normally holds the universal 7 bar seated in the recess 19,

The universal bar 20 is provided with a bracket 22 having a pivotal connection at 23 with an oscillating member 24 pivoted at 25 to the frame of the machine. An escape ment wheel 26 is mounted on the frame member 27 and controls a platen carriage rack 28 which meshes with a pinion 29 secured to the escapement wheel 26. The escapement wheel 26 is controlled by a pair of dogs, not shown, which may be of usual construction, a preferred form of said dogs being illustrated and described in my prior application, Serial No. 246,460, filed July 24, 1918. The escapement dogs are operated by a dog rocker 29 carried on a shaft 30 and having one end thereof arranged to project between fingers 31 and 32- on the lower bifurcated end of the oscillating member 24.

Projections 33 and 34 are provided on the dog rocker 29 for engaging the fingers 31 and 32 respectively on the oscillating member 24. Stops are provided for limiting the oscillatory movement ofthe dog rocker 29 as shown in Fig. 3. It will be apparent that when a key is struck and a type bar is operated to shift the universal bar 20 the finger 32 will move to the right as viewed in Fig. 1, and thus shift the dog rocker and the escapement mechanism. 7 When the type bar is permitted to return to its inactive p0 sition the bracket 22 will move to the left under the influence ofthe spring for the universal bar and cause the finger 31 to en'- gage the projection 33 and again shift the dog rocker to complete the operation of the escapement mechanism.

Under normal conditions it is desirable that the type bars shall be retained in their pivotal relation with the type bar segment and this is effected by the universal bar 20 which bears upon all of the type bars and prevents their disconnection from the pivot rod 12. Normally the universal bar 20 cannot be moved to the right in Fig. 1 a sufiicient distance to permit disconnection of the hook 15 from the pivot rod 12. It is sometimes desirable however to remove a particular type bar for repairs or for replacement or other reasons and provision is made to permit such removal when it becomes deslrable. Stamping 35 is pivoted at 36 to a lug 37 formed on the oscillating member 24. This stamping 36 is provided with a tailpiece 38 which lies between the finger 32 and the projection 34 on the dog rocker 29. A coil spring 39 is secured to the end of the tailpiece 38 and to an eye 40 on the oscillatory member 24 and normally holds the tailpiece in position-adjacent the finger 32. A stop shoulder 41 is formed on. the tail-piece 38 to limit the movement of the stampin 35 under the influence of the dlnder ordinary operation the finger 32 operates through the tail-piece spring 39'.

to move the dog rocker 29. The stamping 35 is' provided with a fingerpiece 42' by which the stamping may be moved about.

its pivot 36 against the tension of the spring 39 to withdraw the tail-piece 38 from be. r 32 and the projection 34..

tween the fin When the tail-piece is thus removed the bracket 22 and the universal bar 20 may be moved to the right, as viewed in Fig. 1, a

distance beyond the normal limit'of its movement, an amount equal to the thickness of the tail-piece 38. This extra movement of the universal bar 20 is sufficient to permit the hook 15 to move to the right as viewed.

in Fig. 1 until it becomes disengaged from the pivot bar 12. The lower end of the type bar '11 is usually so shaped that it is neces-' sary to swing the bar downwardly away from the platen before it can be unhooked from the pivot rod 12. It will be noted that the type bar segment 10 at the upper end of the wheel 14 is provided with an overhanging ledge 43 for preventing foreign material from accumulating in the slot-14 and this overhanging ledge would prevent disconnection of the type bar from the pivot 12 when the type bar is in its printing posi tion where the bars are shaped as shown in the figure of the drawing. vWhen the hook 15 has been disengaged from the pivot rod 12 the type bar will be free to slide downvice, said oscillatory member having fingers for engaging said actuating device; and a stop mova'bl'e'into and out oi position be tween'one'of said fingers arid said dog actuating device. 7

2. The combination with a typewriter having escapement mechanism; of a dog ac tuating device for controlling said escapement mechanism;- a bifurcated oscillatory member positioned to stride said actuatingdevice; a universal bar for moving said bifurcated member; a stop positioned between saiddog actuating device and one branch.

of said bifurcated member-for transmitting movement from said bifurcatedfmember to said dog actuating device, said stop being movable out of positionv to permit excess movement of said bifurcated member and resilient means for retaining'said' stop in position. V a

3. In a typewriter, a type bar segment, a type bar having an open book thereon for pivotally mounting said bar on said Beg-1 merit, a unlversal bar for retaining said hook in'position on its pivotal support. escapement mechanism for'said typewriter, a dogactuatingv member for controlling said es capement mechanism, an oscillatory member having spaced abutments for engaging opposite sides of said dog-actuating member, means for connecting said oscillatory member with said universal bar for moving said oscillatory member when; said type bar is :operated, a stop pivotally connected with said oscillatory member to swing into and out of position between said abutments to vary the amount of opening thcrebetween,

and resilient means i'torholding said stop in position-between said abutments to tran mit movement from-said oscillatory member to said dog-actuating member and .to limit the movement of said'univ'ersal bar to retain said type bar in position on its pivotal mounting.

In testimony whereof I have signed my name to this specificationon' this 9th day of March, A. D. 1920.

OTTO A. nornmson 

